TY - JOUR
T1 - Tin porphyrin immobilization significantly enhances visible-light-photosensitized degradation of Microcystins
T2 - Mechanistic implications
AU - Yoo, Ha Young
AU - Yan, Shuwen
AU - Ra, Ji Woon
AU - Jeon, Dahee
AU - Goh, Byoungsook
AU - Kim, Tae Young
AU - Mackeyev, Yuri
AU - Ahn, Yong Yoon
AU - Kim, Hee Joon
AU - Wilson, Lon J.
AU - Alvarez, Pedro J.J.
AU - Lee, Yunho
AU - Song, Weihua
AU - Hong, Seok Won
AU - Kim, Jungwon
AU - Lee, Jaesang
N1 - Funding Information:
This study was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2014R1A1A2056935); a National Research Foundation of Korea Grant funded by the Korean Government (MSIP) (2016, University-Institute cooperation program); Space Core Technology Development Program (NRF-2014M1A3A3A02034875) through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning; the Mid-Career Researcher Program (NRF-2013R1A2A2A03068929) through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning; Welch Foundation (Grant C-0627) at Rice University; and the NSF ERC on Nanotechnology-Enabled Water Treatment (EEC-1449500).
PY - 2016/12/15
Y1 - 2016/12/15
N2 - This study demonstrates that tin porphyrin (SnP) loading on a silica substrate (SnP/silica) markedly accelerates the degradation of Microcystins (MCs) under visible light irradiation, despite a reduction of photosensitized singlet oxygen (1O2) production. A comparative study using Rose Bengal, SnP, and C60 aminofullerene suggested that the MC-RR decay rate was directly proportional to the photosensitizing activity for triplet state-induced oxidation, while it exhibited poor correlation to singlet oxygenation efficiency. This implies that electron transfer from MC to the triplet state of SnP (facilitated by favorable MC sorption on silica) contributes to the photosensitized MC oxidation. Experiments to examine sensitizers for the one-electron oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) showed the superiority of SnP/silica for photo-initiated electron transfer as a possible MC oxidation route. This was corroborated by the negligible effects of reagents that quench or facilitate singlet oxygenation (e.g., azide ion, D2O) on the MC-RR degradation rate. Despite MC-RR removal below detection levels, residual toxicity (indicated by a significant decrease in protein phosphatase inhibition activity) was observed. Tandem mass spectrometric analysis suggests that this residual toxicity may be ascribed to byproducts resulting from addition of a single oxygen atom to the Adda moiety.
AB - This study demonstrates that tin porphyrin (SnP) loading on a silica substrate (SnP/silica) markedly accelerates the degradation of Microcystins (MCs) under visible light irradiation, despite a reduction of photosensitized singlet oxygen (1O2) production. A comparative study using Rose Bengal, SnP, and C60 aminofullerene suggested that the MC-RR decay rate was directly proportional to the photosensitizing activity for triplet state-induced oxidation, while it exhibited poor correlation to singlet oxygenation efficiency. This implies that electron transfer from MC to the triplet state of SnP (facilitated by favorable MC sorption on silica) contributes to the photosensitized MC oxidation. Experiments to examine sensitizers for the one-electron oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) showed the superiority of SnP/silica for photo-initiated electron transfer as a possible MC oxidation route. This was corroborated by the negligible effects of reagents that quench or facilitate singlet oxygenation (e.g., azide ion, D2O) on the MC-RR degradation rate. Despite MC-RR removal below detection levels, residual toxicity (indicated by a significant decrease in protein phosphatase inhibition activity) was observed. Tandem mass spectrometric analysis suggests that this residual toxicity may be ascribed to byproducts resulting from addition of a single oxygen atom to the Adda moiety.
KW - Electron transfer
KW - Microcystins
KW - Photosensitized degradation
KW - Protein phosphatase inhibition
KW - Singlet oxygen
KW - Tandem mass spectrometry
KW - Visible light responsive sensitizer
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U2 - 10.1016/j.apcatb.2016.06.026
DO - 10.1016/j.apcatb.2016.06.026
M3 - Article
AN - SCOPUS:84975089415
VL - 199
SP - 33
EP - 44
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
SN - 0926-3373
ER -